My Pentair light in my inground pool worked fine last summer. I had the liner replaced this winter, and the light has not worked properly since. We can turn the light on, and it will work for a while, but after some period of time between 5 and 15 minutes, it will trip the GFCI. If I then reset the GFCI and turn the light on, it will flash and go off immediately.

I don't know if this is relevant, but after installing the liner I was losing a small amount of water. The installer returned and sealed a leak at the back of the light niche with epoxy.

I did have some moisture inside the light fixture, which was the first hypothesis for what was causing the problem. I replaced the gasket, and there is now no water in the fixture, but the problem persists.

Thanks for any help.